Reviews and Book Notices. 83 
would extend both wings fully and flatly, and lift them gently 
up and down six or eight times, evidently to feel that ‘ baby’ 
was not clinging in a position which would incur risk to either 
of them ; often she would not be quite satisfied, but would tuck 
her head down, and move it slightly. After these preliminaries 
had been gone through, she would launch off, but seldom flew 
more than five or six lengths of the room, and that with a slow, 
straight, and heavy flight. It was so obviously hard work for 
her that I did not often encourage the proceedings, especially 
as she often had difficulty in turning after flying the length of 
the room, several times being unable to do so, and colliding 
with the wall and falling to the ground, which I feared might 
result in injury to the young one. Sometimes, also, she would 
fly round the room four or five times, gradually falling towards 
the floor, like a bat only half awake. 
When the young ones were very small, however, I once or 
twice got their mothers to fly pretty briskly with them, and as 
this was in the daytime, I had a good view of the procedure, 
and found that the ‘baby’ clung to the mother’s nipple with 
its mouth, and allowing its body to hang quite down, merely 
brought up its feet and clung to her fur with them also. In 
this position the youngster was quite conspicuous, as its mother 
flew about, at close quarters, in the daylight, hanging down 
like a little ball attached to her breast. 
Mr. Wakefield very kindly took photographs of one of my 
young Pipistrelles week by week, and a series of these are 
reproduced on Plate XI., showing it at one, seven, fourteen, 
and twenty-one days old. The gradual increase in size and 
darkening in colour is well shown in these photographs ; but 
the hairiness which should be slightly apparent even in fig. 2 
does not become noticeable until fig. 5. 
Familiar Trees. By Prof. G. S. Boulger. Cassell & Co., London. 
Messrs. Cassell are bringing out, in fortnightly parts at 6d. net each, 
Prof. Boulger’s ‘Familiar Trees.’ The present edition, which has been 
revised throughout and enlarged, is being produced in 29 parts, several 
of which have already been issued. The author's name above is a guarantee 
for the accuracy of the descriptions given. Each species is carefully de- 
scribed and figured, the photographs of the characteristic trees of each 
type being all that can be desired. There are also no fewer than 114 coloured 
plates, mostly admirably done, illustrating the fruit, flowers, foliage, or the 
entire tree. Of great value also are the 114 full-page plates, showing the 
structure of the different woods, from micro-photographs. One of these the 
publishers have kindly enabled us to reproduce (see plate XVIII.). The 
work should have a very large sale, and will doubtless do much to popularise 
the study of the trees which form so picturesque and prominent a feature 
in almost every British landscape. 
1907 March i. 
